locked boot: Not an issue if the phone works as it should. I don't need custom ROMS, rooting, etc. if the phone is completely functional (unlike my Captivate

).
motoblur: Seems as though motoblur is a "package" that allows for integrated contact management. It doesn't really change the UI of the phone (unlike Sense). Just don't use it if you don't like it.
no sideloading: There's always a way around this. I would wait until the phone comes out to say that there will be no sideloading.
gonna have no full ROMs : See the first item on the list.
Only a 5mp camera: I'm not printing posters with the pictures my phone is gong to take. A 5mp can easily print 8 x 11 photos.
plasticky cheap body: Have you actually held the phone? Just because it's plastic, doesn't mean it will feel cheap.
The dual-core CPU and 1 GB RAM ensures that this phone will be able to handle OS and apps of the future. The 1900 mAh battery is a huge plus.